Ophthalmic apparatus with corrective meridians having extended tolerance band with freeform refractive surfaces

Abstract

The embodiments disclosed herein include improved toric lenses and other ophthalmic apparatuses (including, for example, contact lens, intraocular lenses (IOLs), and the like) that includes a freeform-polynomial surface area that establishes a band of operational meridian for the apparatus to an intended correction meridian. The freeform-polynomial surface area is defined by a mathematical expression comprising a combination of one or more polynomial expressions (e.g., Chebyshev-based polynomial expression, Zernike-based polynomial expression, etc.) each having a distinct complex orders.

What is claimed is: 
     
       1. An ophthalmic apparatus having regions of one or more base spherical powers and one or more cylinder powers that are added to the one or more base spherical power for correcting an astigmatism, the apparatus comprising one or more optical zones, including a first optical zone defined by a freeform-polynomial surface area coincident with one or more distinct cylinder powers, wherein light incident to a first region of the freeform-polynomial surface area, and regions nearby to the first region, is directed to a first point of focus such that the regions nearby to the first region direct light to the first point of focus when the freeform-polynomial surface area is rotationally offset from the first region, thereby establishing a band of operational meridian for the apparatus to an intended correction meridian, and wherein the freeform-polynomial surface area is defined as a mathematical expression comprising a combination of one or more polynomial expressions each having a distinct complex orders,
 wherein the ophthalmic apparatus comprises a rotationally-tolerant intraocular lens (IOL), 
 wherein the freeform-polynomial surface area has for each continuously distributed contour line at the IOL plane a difference of less than about 0.6 Diopters, 
 wherein the combination of one or more polynomial expressions defines an angularly-varying phase member that is tolerant of cylindrical axis misalignment (CAM) up to an extended band of operation without degradation of visual acuity (VA) or modular transfer function (MTF). 
 
     
     
       2. The ophthalmic apparatus of  claim 1 , wherein the one or more optical zones includes a second optical zone defined by a second freeform-polynomial surface area, wherein the second freeform-polynomial surface area is characterized and defined by a second polynomial. 
     
     
       3. The ophthalmic apparatus of  claim 2 , wherein the second freeform-polynomial surface area has a second height profile that varies according to a freeform polynomial selected from the group consisting of a Chebyshev polynomial and a Zernike polynomial. 
     
     
       4. The ophthalmic apparatus of  claim 2 , wherein light incident to a second region of the second freeform-polynomial surface area, and regions nearby to the second region, is directed to a second point of focus such that the regions nearby to the second region direct light to the second point of focus when the second freeform-polynomial surface area is rotationally offset from the second region. 
     
     
       5. The ophthalmic apparatus of  claim 2 , wherein light incident to a second region of the second freeform-polynomial surface area, and regions nearby to the second region, is directed to the first point of focus such that the regions nearby to the second region direct light to the first point of focus when the second freeform-polynomial surface area is rotationally offset from the second region. 
     
     
       6. The ophthalmic apparatus of  claim 2 , wherein the second freeform-polynomial surface area has a third height profile T 2 (x,y) superimposed on a first height profile, the third height profile being defined as:
     T   2 ( x,y )=Σ{ c   2 ( i   2   ,j   2 )*cos( i   2 *arccos( t   2 ))*cos( j   2 *arccos( t   2 ))}
 
 
       where c 2 (i,j) is a coefficient based on i 2  and j 2 , which are each integers, x and y are spatial locations on the second freeform-polynomial surface area and has values between −1.0 and 1.0, and t 2  is a normalized parameter having values between −1.0 and 1.0. 
     
     
       7. The ophthalmic apparatus of  claim 2 , wherein the second freeform-polynomial surface area comprise a monofocal lens, a bifocal lens, or a multi-focal lens. 
     
     
       8. The ophthalmic apparatus of  claim 2 , wherein the second freeform-polynomial surface area comprise an extended range of vision lens. 
     
     
       9. The ophthalmic apparatus of  claim 1 , wherein the one or more optical zones includes a second optical zone defined by a second freeform-polynomial surface area, wherein the second freeform-polynomial surface area is characterized and defined by a second combination of one or more polynomial expressions each having a distinct complex orders. 
     
     
       10. The ophthalmic apparatus of  claim 9 , wherein at least one of the one or more polynomial expression is selected from the group consisting of a Cheby shev polynomial and a Zernike polynomial.